
硅橡膠是指主鏈由硅(gui)(gui)(gui)和氧(yang)原(yuan)子(zi)交替(ti)構成(cheng),硅(gui)(gui)(gui)原(yuan)子(zi)上通常連有(you)(you)兩個有(you)(you)機基(ji)(ji)(ji)團的(de)橡(xiang)膠(jiao)(jiao)(jiao)。普通的(de)硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)主要由含甲基(ji)(ji)(ji)和少量乙烯基(ji)(ji)(ji)的(de)硅(gui)(gui)(gui)氧(yang)鏈節組成(cheng)。苯基(ji)(ji)(ji)的(de)引(yin)入可提高硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)耐(nai)高、低(di)溫(wen)(wen)性(xing)(xing)能(neng)(neng),三氟(fu)丙基(ji)(ji)(ji)及氰基(ji)(ji)(ji)的(de)引(yin)入則可提高硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)耐(nai)溫(wen)(wen)及耐(nai)油性(xing)(xing)能(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)耐(nai)低(di)溫(wen)(wen)性(xing)(xing)能(neng)(neng)良好,一般在-55℃下仍能(neng)(neng)工(gong)作。引(yin)入苯基(ji)(ji)(ji)后,可達(da)-73℃。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)耐(nai)熱性(xing)(xing)能(neng)(neng)也很(hen)突出(chu),在180℃下可長(chang)期(qi)工(gong)作,稍高于200℃也能(neng)(neng)承受數周(zhou)或(huo)更長(chang)時間仍有(you)(you)彈性(xing)(xing),瞬時可耐(nai)300℃以上的(de)高溫(wen)(wen)。硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)的(de)透氣性(xing)(xing)好,氧(yang)氣透過率在合(he)(he)成(cheng)聚合(he)(he)物中是較高的(de)。此外,硅(gui)(gui)(gui)橡(xiang)膠(jiao)(jiao)(jiao)還具有(you)(you)生理(li)惰性(xing)(xing)、不會導致凝血的(de)突出(chu)特(te)性(xing)(xing),因此在醫(yi)用領(ling)域應(ying)用廣泛(fan)。
主要品種
硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)分類(lei)的(de)方(fang)法很多,通常(chang)按(an)固(gu)化(hua)前(qian)的(de)形態分為固(gu)體(ti)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)和液體(ti)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao);按(an)硫(liu)化(hua)溫(wen)(wen)度(du)分為室(shi)溫(wen)(wen)硫(liu)化(hua)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao),高(gao)溫(wen)(wen)硫(liu)化(hua)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao);按(an)所用單體(ti)的(de)不(bu)同(tong),可(ke)分為甲基(ji)乙(yi)(yi)烯基(ji)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao),甲基(ji)苯基(ji)乙(yi)(yi)烯基(ji)硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)、氟硅(gui)(gui),腈硅(gui)(gui)橡(xiang)(xiang)(xiang)(xiang)膠(jiao)等;按(an)性(xing)能(neng)和用途的(de)不(bu)同(tong)又可(ke)分為通用型(xing)(xing)(xing)、超耐低溫(wen)(wen)型(xing)(xing)(xing)、超耐高(gao)溫(wen)(wen)型(xing)(xing)(xing)、高(gao)強力型(xing)(xing)(xing)、耐油(you)型(xing)(xing)(xing)、醫(yi)用型(xing)(xing)(xing)等等。
發展史
硅(gui)(gui)橡膠(jiao)(jiao)(jiao)早(zao)期是(shi)由(you)美國(guo)(guo)以三氯化鐵為催化劑合成(cheng)(cheng)的(de)(de)。1945年,硅(gui)(gui)橡膠(jiao)(jiao)(jiao)產(chan)品問世。1948年,采用高比表面積的(de)(de)氣相法白炭黑(hei)補強的(de)(de)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)研制成(cheng)(cheng)功(gong),使硅(gui)(gui)橡膠(jiao)(jiao)(jiao)的(de)(de)性能(neng)躍升到實用階段,奠定了現代硅(gui)(gui)橡膠(jiao)(jiao)(jiao)生(sheng)產(chan)技術的(de)(de)基礎(chu)。從二甲(jia)基二氯硅(gui)(gui)烷合成(cheng)(cheng)開始生(sheng)產(chan)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)的(de)(de)國(guo)(guo)家有美國(guo)(guo)。俄羅(luo)斯、德國(guo)(guo)、日(ri)本、韓國(guo)(guo)和中(zhong)(zhong)國(guo)(guo)等。中(zhong)(zhong)國(guo)(guo)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)的(de)(de)工業化研究(jiu)始于1957年,多(duo)家研究(jiu)所和企業陸續開發出各種硅(gui)(gui)橡膠(jiao)(jiao)(jiao)。到2003年底,中(zhong)(zhong)國(guo)(guo)硅(gui)(gui)橡膠(jiao)(jiao)(jiao)生(sheng)產(chan)能(neng)力為135千(qian)噸,其中(zhong)(zhong)高溫膠(jiao)(jiao)(jiao)100千(qian)噸。
高溫硫化硅橡膠
高(gao)溫硫化(hua)(hua)(hua)硅橡膠(jiao)是(shi)(shi)指聚(ju)硅氧(yang)烷變成(cheng)彈(dan)(dan)性(xing)(xing)(xing)體的過程是(shi)(shi)經過高(gao)溫(110-170℃)硫化(hua)(hua)(hua)成(cheng)型的。它主要(yao)以高(gao)分子量(liang)的聚(ju)甲基(ji)乙烯基(ji)硅氧(yang)烷為生(sheng)膠(jiao),混入(ru)補強(qiang)填料、硫化(hua)(hua)(hua)劑(ji)(ji)等,在(zai)加熱(re)加壓下硫化(hua)(hua)(hua)成(cheng)彈(dan)(dan)性(xing)(xing)(xing)體。硅橡膠(jiao)的補強(qiang)主要(yao)是(shi)(shi)各(ge)種(zhong)(zhong)類型的白炭黑(hei),可使硫化(hua)(hua)(hua)膠(jiao)的強(qiang)度增加數(shu)十(shi)倍。有時為了降低成(cheng)本或(huo)改善膠(jiao)料性(xing)(xing)(xing)能及賦予硫化(hua)(hua)(hua)膠(jiao)各(ge)種(zhong)(zhong)特(te)殊的性(xing)(xing)(xing)能,也加入(ru)相(xiang)應的各(ge)種(zhong)(zhong)添加劑(ji)(ji)。硫化(hua)(hua)(hua)劑(ji)(ji)是(shi)(shi)各(ge)種(zhong)(zhong)有機過氧(yang)化(hua)(hua)(hua)物或(huo)加成(cheng)反應催化(hua)(hua)(hua)劑(ji)(ji)。
加工成型方法(fa)如圖(tu)所示。一次硫化(hua)的(de)(de)目的(de)(de)是(shi)進行高分子鏈的(de)(de)交聯(lian)反應;二次硫化(hua)的(de)(de)目的(de)(de)是(shi)進行補充交聯(lian)、驅(qu)除(chu)硫化(hua)劑(ji)分解(jie)產物和其(qi)他揮(hui)發(fa)性化(hua)合物以穩(wen)定硫化(hua)膠的(de)(de)各項性能。常用的(de)(de)設備(bei)有開放式煉(lian)膠機(ji)、捏合機(ji)及(ji)真空密煉(lian)機(ji)。
主要性能
(1)高溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)顯著的(de)(de)(de)特征(zheng)是高溫(wen)(wen)(wen)穩(wen)定(ding)性(xing)(xing)(xing)(xing)(xing)(xing),雖(sui)然(ran)(ran)常溫(wen)(wen)(wen)下(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)強度(du)僅是天(tian)(tian)然(ran)(ran)橡(xiang)(xiang)(xiang)膠(jiao)或某些合成橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)一(yi)(yi)半(ban),但在200℃以上的(de)(de)(de)高溫(wen)(wen)(wen)環境(jing)下(xia),硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)仍能(neng)(neng)(neng)(neng)保持(chi)一(yi)(yi)定(ding)的(de)(de)(de)柔韌性(xing)(xing)(xing)(xing)(xing)(xing)、回彈性(xing)(xing)(xing)(xing)(xing)(xing)和表面(mian)硬度(du),且(qie)力學性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)無明顯變化(hua)。(2)低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)的(de)(de)(de)玻璃(li)化(hua)溫(wen)(wen)(wen)度(du)一(yi)(yi)般為-70~-50℃,特殊配方(fang)可達-100℃,表明其低溫(wen)(wen)(wen)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優(you)異。這對航(hang)空(kong)、宇航(hang)工業的(de)(de)(de)意(yi)義重大(da)。(3)耐(nai)(nai)(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)中Si-O-Si鍵對氧(yang)(yang)、臭氧(yang)(yang)及紫外線等十分穩(wen)定(ding),在不加任何(he)添(tian)加劑的(de)(de)(de)情況下(xia),就(jiu)具有優(you)良的(de)(de)(de)耐(nai)(nai)(nai)候(hou)性(xing)(xing)(xing)(xing)(xing)(xing)。(4)電(dian)(dian)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)具有優(you)異的(de)(de)(de)絕(jue)緣性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng),耐(nai)(nai)(nai)電(dian)(dian)暈(yun)性(xing)(xing)(xing)(xing)(xing)(xing)和耐(nai)(nai)(nai)電(dian)(dian)弧(hu)性(xing)(xing)(xing)(xing)(xing)(xing)也非(fei)常好。(5)物理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)常溫(wen)(wen)(wen)下(xia)的(de)(de)(de)物理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)比(bi)通(tong)(tong)用橡(xiang)(xiang)(xiang)膠(jiao)差(cha),但在150℃的(de)(de)(de)高溫(wen)(wen)(wen)和-50℃的(de)(de)(de)低溫(wen)(wen)(wen)下(xia),其物理機(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)優(you)于通(tong)(tong)用橡(xiang)(xiang)(xiang)膠(jiao)。(6)耐(nai)(nai)(nai)油及化(hua)學試(shi)劑性(xing)(xing)(xing)(xing)(xing)(xing)。普通(tong)(tong)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)具有中等的(de)(de)(de)耐(nai)(nai)(nai)油、耐(nai)(nai)(nai)溶劑性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。(7)氣(qi)體(ti)(ti)透(tou)過性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)(neng)(neng)(neng)。室溫(wen)(wen)(wen)下(xia)硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)對空(kong)氣(qi)、氮、氧(yang)(yang)、二氧(yang)(yang)化(hua)碳等氣(qi)體(ti)(ti)的(de)(de)(de)透(tou)氣(qi)性(xing)(xing)(xing)(xing)(xing)(xing)比(bi)天(tian)(tian)然(ran)(ran)橡(xiang)(xiang)(xiang)膠(jiao)高出(chu)30-50倍。(8)生理惰(duo)性(xing)(xing)(xing)(xing)(xing)(xing)。硅(gui)(gui)(gui)橡(xiang)(xiang)(xiang)膠(jiao)無毒,無味(wei),無嗅(xiu),與人體(ti)(ti)組織不粘連,具有抗凝血作用,對肌體(ti)(ti)組織的(de)(de)(de)反應性(xing)(xing)(xing)(xing)(xing)(xing)非(fei)常少(shao)。特別適合作為醫(yi)用材料(liao)。
硅橡膠的用量
據中國(guo)汽(qi)(qi)(qi)(qi)車(che)(che)(che)工業(ye)協(xie)會統(tong)計,2012年(nian),汽(qi)(qi)(qi)(qi)車(che)(che)(che)產銷分別(bie)達(da)到1927.18萬(wan)(wan)輛和1930.64萬(wan)(wan)輛,同比分別(bie)增(zeng)(zeng)長4.63%和4.33%,汽(qi)(qi)(qi)(qi)車(che)(che)(che)工業(ye)硅橡(xiang)(xiang)膠的(de)(de)(de)用(yong)量(liang)約達(da)2.0萬(wan)(wan)t。根據觀研天(tian)下的(de)(de)(de)新研究(jiu),增(zeng)(zeng)加有(you)機(ji)(ji)硅材料在(zai)汽(qi)(qi)(qi)(qi)車(che)(che)(che)零部件(jian)方面的(de)(de)(de)用(yong)量(liang),可以(yi)(yi)大幅度提(ti)(ti)高汽(qi)(qi)(qi)(qi)車(che)(che)(che)的(de)(de)(de)安(an)全性能,因此,汽(qi)(qi)(qi)(qi)車(che)(che)(che)產量(liang)和單車(che)(che)(che)用(yong)量(liang)水(shui)平的(de)(de)(de)提(ti)(ti)高都將(jiang)推動汽(qi)(qi)(qi)(qi)車(che)(che)(che)工業(ye)對硅橡(xiang)(xiang)膠需(xu)求的(de)(de)(de)增(zeng)(zeng)加。國(guo)家鼓勵自主(zhu)品(pin)牌(pai)的(de)(de)(de)汽(qi)(qi)(qi)(qi)車(che)(che)(che)發展(zhan),關(guan)鍵汽(qi)(qi)(qi)(qi)車(che)(che)(che)零部件(jian)實現(xian)自主(zhu)化,《2012年(nian)度黨政機(ji)(ji)關(guan)公務用(yong)車(che)(che)(che)選(xuan)用(yong)車(che)(che)(che)型目錄(征求意見稿(gao))》為(wei)自主(zhu)品(pin)牌(pai)擴大在(zai)政府采(cai)購的(de)(de)(de)市場份額,為(wei)改變目前國(guo)內(nei)政府采(cai)購以(yi)(yi)合資品(pin)牌(pai)產品(pin)為(wei)主(zhu)的(de)(de)(de)局面提(ti)(ti)供了(le)保障(zhang)。促進自主(zhu)品(pin)牌(pai)發展(zhan),國(guo)產汽(qi)(qi)(qi)(qi)車(che)(che)(che)業(ye)的(de)(de)(de)繁榮(rong)將(jiang)為(wei)汽(qi)(qi)(qi)(qi)車(che)(che)(che)膠的(de)(de)(de)應用(yong)提(ti)(ti)供有(you)力保障(zhang)。預測(ce)未來3年(nian),我國(guo)室(shi)溫硫化硅橡(xiang)(xiang)膠在(zai)汽(qi)(qi)(qi)(qi)車(che)(che)(che)行業(ye)將(jiang)以(yi)(yi)年(nian)均20%增(zeng)(zeng)長。
此外,硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)是重(zhong)要的(de)(de)(de)非石(shi)(shi)油基(ji)合成橡(xiang)(xiang)膠(jiao)(jiao),約占非石(shi)(shi)油基(ji)合成橡(xiang)(xiang)膠(jiao)(jiao)消費(fei)(fei)量(liang)的(de)(de)(de)98%。但因為(wei)石(shi)(shi)油價(jia)格的(de)(de)(de)大(da)(da)幅上(shang)漲,同(tong)時我(wo)國在硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)關鍵原料有(you)機(ji)硅(gui)(gui)(gui)單體(ti)(ti)的(de)(de)(de)生產(chan)(chan)技術(shu)方面(mian)取得突破,有(you)機(ji)硅(gui)(gui)(gui)單體(ti)(ti)的(de)(de)(de)生產(chan)(chan)技術(shu)在2005年前(qian)被幾家(jia)跨國公司壟斷,但目前(qian)我(wo)國已(yi)發(fa)展成為(wei)全球有(you)機(ji)硅(gui)(gui)(gui)單體(ti)(ti)第1大(da)(da)國,這2個方面(mian)原因使硅(gui)(gui)(gui)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)價(jia)格從2011年起開(kai)(kai)始低于石(shi)(shi)油基(ji)合成橡(xiang)(xiang)膠(jiao)(jiao),僅(jin)約為(wei)大(da)(da)宗石(shi)(shi)油基(ji)橡(xiang)(xiang)膠(jiao)(jiao)的(de)(de)(de)80%~90%,成為(wei)廉價(jia)的(de)(de)(de)合成橡(xiang)(xiang)膠(jiao)(jiao),并開(kai)(kai)始大(da)(da)規模替代石(shi)(shi)油基(ji)合成橡(xiang)(xiang)膠(jiao)(jiao)。這將極大(da)(da)拓展有(you)機(ji)硅(gui)(gui)(gui)產(chan)(chan)業的(de)(de)(de)市場空間,同(tong)時將帶(dai)動硅(gui)(gui)(gui)油、硅(gui)(gui)(gui)烷偶聯(lian)劑和(he)硅(gui)(gui)(gui)樹脂等其他有(you)機(ji)硅(gui)(gui)(gui)產(chan)(chan)品的(de)(de)(de)消費(fei)(fei)。